Pipe wrench



MEAD PIPE WRENCH Filed Feb. 1'7, 1941 INVENTOR.

' ATTORNEY.

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Patented Apr. 6, 1943 UNITED STATES FATENT OFFIQE PIPE WRENCH Lawrence Mead, Whittier, Calif. Application February 1'2, 1941, Serial No. 379,273

3 Claims.

This invention relates to pipe wrenches, and particularly to one of that type provided with a. quick adjustment feature in the form of teeth along the shank of the movable jaw, and a cooperating pawl or holding member on the frame or yoke of the wrench.

The major object of my invention is to im prove the arrangement of the teeth and pawl relative to each other and to the axis of the frame so that all slack between different adjusted positions is practically eliminated,v and a more accurate or close adjustment of the wrench is possible than is the case with previous wrenches of this type. Also I am able to use relatively large holding teeth, without an excessive relative movement of the jaw shank and frame being necessary for the teeth to clear the pawl.

I have also provided an extremely simple and effective means to prevent separation of the parts, while enabling such separation to be easily effected when desired.

A further object of the invention is to produce a simple and inexpensive device and yet one which will be exceedingly effective for the purpose for which it is designed.

These objects I accomplish by means of such structure and relative arrangement of parts as will full appear by a perusal of the following specification and claims.

In the drawing similar characters of reference indicate corresponding parts in the several views:

Fig. 1 is a fragmentary side elevation of my improved wrench partly in section. and showing the movable jaw held against sliding movement.

Fig. 2 is a similar view showing the holding pawl released from the shank teeth.

Fig. '3 is a fragmentary cross-section on' the line 3-3 of Fig. 1.

Referring now more particularly to the characters of reference on the drawing, the wrench comprises a handle I terminating in a relatively deep portion 2 which has a fixed jaw 3 on its outer end, one edge with the corresponding edge of said portion 2. Mounted in the portion 2 intermediate its ends and adjacent the opposite edge thereof is a pin 4 which forms the pivot mounting for a frame or yoke 5 of U-shaped cross section. The portion 2 is formed with a rounding edge 6 concentric with the pin 4 and which then slopes tangentially as at I to a junction with the adjacent edge of the handle.

Slidable in the yoke is the shank 8 of the movable jaw 9, which of course is adapted to cooperate with the jaw 3. One edge of the shank of the handle being alinedrests on and can rock somewhat about the rounded edge 6 in the direction of the Slope 1, while the opposite edge of the shank is spaced from and is normally parallel to the inner top edge of the yoke.

Formed in said oppositeedge of the shank isa row of teeth In, several of which at a time are adapted to cooperate with the teeth H of a holding member 12. This member is disposed between the sides of the yoke and is formed a substantially semi-spherical head l3, which is swivelly socketed in the top of the yoke adjacent its forward end and head of the pin 4. The head is deeply seated so that there is no tendency for it to slip out when a longitudinal pulling strain is placed on the shank 8 and member i2. The head is held in position by an axial stem 14 projecting through a relatively large opening in the top of the yoke and having a nut F5 on its outer end which bears against a spring strip l6 so that the head is free to swivel in any direction but is held firmly in position without danger of binding.

A fiat spring H is mounted at its forward end in the yoke just rearwardly of the member i2 and bears at its rear end against the adjacent edge of the shank 8 beyond the teeth It). A lug 18 projects outwardly from said edge of the shank at its rear end and limits the outward sliding movement of the shank by reason of the engagement of saidlug with the adjacent end of the spring, while at the same time permitting of complete withdrawal of the shank from the yoke if said end. of the spring is pried up clear of the lug. The spring and teeth are arranged so that when the spring abuts against said ice, the teeth oi the holding member and those of the shank will be in mesh, and no strain tending to buckle.

the spring is then placed on the same. The spring of course acts to rotate the yoke relative to the shank so as to hold the teeth of the member 12 in firm mesh with the shank teeth, and also causes the shank to be held in firm contact with the rounding edge 6. Both the shank and yoke may thus rock freely about the pin 4.

The cooperating working faces of the teeth I!) and I I are cut at an angle such that the leading tooth of the member I2 is substantially in a path concentric with the pin 4, or approximately at right angles to a line drawn radially from the pin to the point of such tooth, as indicated in Fig. 2. By reason of this arrangement a swinging of the yoke downwardly toward the rear end relative to the shank, causes the meshing teeth to disengage each other without any longitudinal movement of the shank being required to effect the necessary clearance. The working faces of the teeth thus incline away from the jaws, but the arrangement as a whole is such that the shank may still be slid rearwardly, or so that the jaws approach each other, without any manual depression or rotation of the yoke being necessary. It will also be noted, as is particularly clear from Fig. 2, that the working faces of the teeth are longer than the opposite faces. This provides a maximum holdin area and a minimum of spacing between the teeth, thus making for close adjustments.

Due to the swivel or universal mounting of the pawl member, the turning of the yoke relative to the shank allows said member to remain substantially parallel to the shank before any lift, and such lift, when it occurs, causes all the teeth to be moved to a clear position substantially simultaneously as shown in Fig. 2. the use of deep teeth without any relatively great shank movement being necessary.

The member I 2 is arranged in the yoke so that it can have some side play, so that when a side pressure is placed on the wrench it tends to cause the yoke to spring and the teeth will still be maintained equally engaged from side to side of the shank.

A light spring l9, weaker than the spring I1,

is disposed between the shank 8 and the handle portion 2 so as to normally maintain the shank in such a position that the jaws are substantially parallel to each other, as shown in Fig. 1. When the yoke 5 is depressed at its rear end to efiect a tooth release, the spring l9 compresses before the spring l1, thus disposing the shank at an angle to the handle or in flat engagement with the slope 7 before the yoke turns relative to the shank. Since said slope and the adjacent edge of the shank are straight the jaws thus always assume the same angle relative to each other when making an adjustment and irrespective of the adjusted position of the shank. The longitudinal line of the shank then cuts diagonally across the longitudinal line of the handle.

Formed with the jaw 3 on each side and at the end thereof nearest the shank 8 is a projecting lug forming a work-engaging shoulder inclining in the direction ofthe movable jaw and adapted to engage the adjacent portion of a pipe or other circular object held between the jaws, as indicated in Fig. 1. This is particularly valuable for small sizes of pipe in that it holds the same further out on the jaws and thus gives a better grip than would otherwise be the case.

From the foregoing description it will be readily seen that I have produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail This allows of may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Having thus described my invention what I claim as new and useful and desire to secure by Letters Patent is:

1. A wrench including a handle having a fixed jaw on one end, a yoke, means pivoting the yoke on the handle adjacent one edge thereof and adjacent the jaw, a shank slidable in the yoke, a movable jaw on the outer end of the shank, a row of teeth along the outer edge of the shank, a cooperating tooth mounted in the yoke between the pivot and the jaws, the shank being spaced from the top of the yoke, and a compression spring disposed in the space between and bearing against the top of the yoke and the adjacent face of the shank, the pivot means being disposed between the points of engagement of the spring and yoke tooth with the shank whereby to cause the yoke adjacent the tooth thereon to turn toward the shank.

2. A wrench including a handle having a fixed jaw on one end, a yoke, means pivoting the yoke on the handle adjacent one edge thereof and adjacent the jaw, a shank slidable in the yoke, a movable jaw on the outer end of the shank, a row of teeth along the outer edge of the shank, a cooperating tooth mounted in the yoke between the pivot and the jaws, the shank being spaced from the top of the yoke, whereby the latter may be turned in one direction relative to the shank; the adjacent edge of the handle being curved concentric with the pivot and the edge of the shank opposite the toothed edge rockably resting on said curved edge, spring means between the yoke and shank tending to turn the yoke in a direction to hold the tooth thereon in mesh with the shank teeth and a relatively weak spring between the handle and shank acting on the latter to rock the same in a direction to maintain the jaws substantially parallel; said pivot means and curved edge being located between the points of engagement of the yoke tooth and said spring means with the shank.

3. A wrench including a handle having a fixed jaw on one end, a yoke, means pivoting the yoke on the handle adjacent one edge thereof and adjacent the jaw, a shank slidable in the yoke, a movable jaw on the outer end of the shank, a row of teeth along the outer edge of the shank, a member having a tooth, a substantially semispherical head on the member and means seating and mounting said head in the yoke for limited universal movement relative thereto; said means comprising a seat in the top of the yoke'for said head, a radial stem on the head projecting freely through an opening in the top of the yoke, an enlarged element on the upper end of the stem and a compression spring between said element and yoke.

LAWRENCE C. MEAD. 

